MOOSIC, Pa. — Why is he here? In a hot minor league stadium surrounded by desperation, perspiration and players not good enough to make even the beat-down version of the Yankees.

Why is he trying to get there? To The Ballpark in Arlington, where Yu Darvish and a crowd that particularly loathes him await on Monday night?

The walls are closing on Alex Rodriguez — age, declining skill, MLB’s steroid police, angry fans, inquiring media. He has every reason to take a golden parachute. To say his hip hurts, get a medical absolution to disappear. Take his money to an island. Surround himself with women, umbrella drinks and — most important — silence. No more closing walls.

Instead, in a clubhouse here, he ponders the issue when I ask about bailing, trying to protect as much of his remaining salary and reputation as possible. Getting out rather than risking all that is on the table in public — that he can’t play, that he will remain the largest, most-hated target in sports, that by playing he will only make the Commissioner’s Office more voracious to take him down.

“I just know I love the game,” Rodriguez told The Post. “This is my first love. Like any first love, it doesn’t have to be rational, so it is not rational.”

Or it is.

Look, if you loathe Alex Rodriguez, you probably feel you have good reason. It might turn out he is one of the worst drug cheats in the history of sports. MLB certainly believes that. He might strike you as a raving phony, not worth believing a single word he says. You could feel your goodwill has been used up, spit out, exhausted.

Got it. This is not a column designed to defend A-Rod. It is simply to say the one thing I think is truly real is that love of the game. That passion, I believe, is pure. Does he want all the trappings? The money? The fame? The attention? You bet.

But he also wants 7 p.m. and “Play ball.”

Again, he can go hide. Friends of his say there is a life beyond baseball for A-Rod. That he will not curl up in a corner. He fancies himself an entrepreneur, dreams of a post-career in the Magic Johnson mold. He collects art, owns fitness centers and real estate, is tied strongly to charity work with the Boys & Girls Club in Miami.

His associates insist he has enough dough and interests to walk away and fill his free time without having to face boos and allegations.

But as A-Rod told me before DHing for the Scranton/Wilkes-Barre Railriders, “Then there wouldn’t be baseball.” There wouldn’t be the passion of his life.

“I know not everyone might understand this, people might think I am crazy,” Rodriguez said. “But I really love this. I love all of it, the practice, the games. And I feel if I can help my team a little, then I owe it to the team and the fans to try.”

You can never be positive about stuff with A-Rod, about how much is pre-planned, packaged to strike just the right chord. But I am positive about that love, that the game remains central to his being.

I have had enough conversations with him over the years about minutiae — proper cutoffs, the right time to hit-and-run, etc. — to sense his gym-rat passions. His face and body perk up when he talks the game. They did yesterday when he started discussing prospects he has seen during his rehab who he calculates can help the Yankees over the next few years. He was channeling his inner GM.

And he loves the day-to-day grind to ready for “Play ball.” It might be taken away from him soon by the reality of age or Bud Selig’s police. For now, though, A-Rod claims there is still a winning baseball player inside him, someone who can succeed beginning Monday night in his one-time home and current boo-atorium of Arlington.

“It’s a process, but a process I think is on the right track,” Rodriguez said.

So he took grounders at third side-by-side with a more spry Adonis Garcia. What used to make Rodriguez stand out was that for his size, he also had burst and grace. I remember him working on the back fields in Tampa at 7 a.m. with Larry Bowa in 2004, trying to learn third base. He was a thoroughbred, powerful but agile. That is gone.

But even after two hip surgeries, he moved fine. His movements were not clunky, sectional. As the DH last night, he went 2-for-4, blooping a single to right and crushing a single to left on which he was thrown out at second trying to stretch. He did get to slide, which was a hurdle, and popped up smiling. He admitted afterward his speed is gone, but he ran better than I anticipated — with a heaviness, not with awkwardness.

Through it all — even in a minor league stadium with various walls closing in on him — he offered pep and enthusiasm. He wrapped his arms around his first love, maybe tighter than ever because he is trying to hold onto something dear slipping away.

He says he knows his detractors always will hate him. But with gray in his chin stubble, he brightens when I ask one more time why he doesn’t run, escape all this, get away from the accusations, insinuations, jeers.

“I want to keep getting up and paying the price to play,” Rodriguez said. “Do you understand?”